The invention relates to an uninterruptible power supply. In such apparatus energy is automatically derived from a standby battery and converted into AC power by an inverter whenever the commercial AC power supply fails.
In the uninterruptible power supply of the prior art many components are required which bear on cost and reliability. The power efficiency of the prior art equipment is less than 85% as a result of the power losses caused by the basic circuits involved, such as a rectifier, a battery charger, etc.
An object of the present invention is to provide an uninterruptible power supply (UPS) apparatus having fewer essential components than heretofore.
Another object of the present invention is to provide UPS apparatus of reduced power losses.
The invention is particularly useful for the supply of power to loads of large size.